The lowest note of a guitar and a bass, which are four-step-tuned stringed instruments, is E (E2 for a guitar and E1 for a bass).
In order to produce a sound lower than the lowest note of a guitar, the low-pitched sound range may be extended by methods such as adding one low-pitched string thereto to form a seven-string guitar or tuning the sixth string of the guitar to a lower tone.
In addition, the low-pitched sound range may be extended by a method of adopting five-step tuning for each of the string intervals to which four-step tuning has been applied.
In addition to these, there is a bass guitar which is given an extended low-pitched sound range by increasing the lengths of all the strings thereof and tuning the notes of the strings to notes that are four steps lower and which accordingly has an even larger main body.
In a case of a bass, there is a method of extending the low-pitched sound range by changing a conventional four-string bass to a five-string or a six-string bass.
Herein, the difference between a four-step-tuned stringed instrument and a five-step-tuned stringed instrument will be described.
A four-step-tuned stringed instrument is a stringed instrument which is tuned with an interval of notes that are four steps lower, by setting, from the side of a lower note string, the first string to C (do), the next string to F (fa), the next string to Bb (si b), the next string to Eb (mi b), and the like, and a five-step-tuned stringed instrument is a stringed instrument which is tuned with an interval of notes that are five steps lower, by setting from the side of a lower note string, the first string to C (do), the next string to G (sol), the next string to D (re), the next string to A (la), and the like.
[Patent Citation 1] JP-UM-A-5-17690